LIG3

This gene is a member of the DNA ligase family. Each member of this family encodes a protein that catalyzes the joining of DNA ends but they each have a distinct role in DNA metabolism. The protein encoded by this gene is involved in excision repair and is located in both the mitochondria and nucleus, with translation initiation from the upstream start codon allowing for transport to the mitochondria and translation initiation from a downstream start codon allowing for transport to the nucleus. Additionally, alternate transcriptional splice variants, encoding different isoforms, have been characterized.

LIG3

Isoform 3 functions as heterodimer with DNA-repair protein XRCC1 in the nucleus and can correct defective DNA strand-break repair and sister chromatid exchange following treatment with ionizing radiation and alkylating agents. Isoform 1 is targeted to mitochondria, where it functions as DNA ligase in mitochondrial base-excision DNA repair (PubMed:10207110, PubMed:24674627).

Base-excision repair, DNA ligationManual Assertion Based On ExperimentIDA:BHF-UCL
Base-excision repair, gap-fillingTAS:Reactome
Cell cycleIEA:UniProtKB-KW
Cell divisionIEA:UniProtKB-KW
DNA biosynthetic processIEA:InterPro
DNA ligationManual Assertion Based On ExperimentIDA:BHF-UCL
Double-strand break repairManual Assertion Based On ExperimentIDA:BHF-UCL
Double-strand break repair via alternative nonhomologous end joiningManual Assertion Based On ExperimentIGI:BHF-UCL
Double-strand break repair via homologous recombinationTAS:Reactome
Lagging strand elongationManual Assertion Based On ExperimentIBA:GO_Central
Mitochondrial DNA repairManual Assertion Based On ExperimentIMP:BHF-UCL
Mitochondrion organizationIDA:BHF-UCL
Negative regulation of mitochondrial DNA replicationManual Assertion Based On ExperimentIMP:CACAO

Isoform 1&2:
Mitochondrion
Contains an N-terminal mitochondrial transit peptide.
Isoform 3&4:
Nucleus
Lacks the N-terminal mitochondrial transit peptide.